John Lambert dropped out of high school in his freshman year, battled addictions to cocaine and alcohol, and was in and out of treatment centers as well as court for minor scrapes with the law.

Last year, when he was locked up in Cook County Jail for possessing cocaine and violating probation, his frustrated family chose not to bail him out, thinking he was better off where he could not abuse drugs or alcohol.

That proved to be a fatal mistake.

On June 26, 2007, his 25th birthday, Lambert was found unconscious in his cell with massive head injuries. After he died 12 days later, a pathologist concluded that Lambert had been beaten to death.

"It's a homicide," Mitra Kalelkar, the deputy chief medical examiner who conducted the autopsy, said in an interview.

The investigation would seem to be straightforward—Lambert had a lone cellmate the night of his fatal injuries.

But the cellmate, David Jamison, told investigators that Lambert sustained the injuries when he fell from the top bunk in their cell.

More than a year later, no one has been charged in his slaying.

"You know what it feels like to know that if you could have bailed him out, he would be alive?" said Lambert's sister, Heather Brenka, her voice cracking with emotion.

Lambert's death was among numerous examples cited in a scathing Justice Department report this summer that found violence rampant at the nation's largest jail. The investigation also ripped the jail for dispensing medical care so substandard that some inmates died needlessly. [Mark Godsey]